Diamonds sparkle and display brilliance, but so do
diamond simulants. How to tell the difference.

Most people have heard of synthetic diamonds, these have the same chemical
compounds and crystal structures as natural diamonds. Diamond Simulants on the
other hand do not have any of the diamond’s chemical or physical properties
and are made from a wide variety of materials. Sometimes it is easy to tell the
difference; other times it requires gemological testing equipment and a trained
eye to pick out the simulants from natural diamonds

So what are some of the tell tale signs to look for that tell you if have a
simulant in your hand and not a real diamond? We know that a diamond is the
hardest natural gemstone and has a 10 rating on the Mohr’s scale. As most
simulants are made from other materials they will be softer than a diamond.
Diamonds will have sharp facets and a superior polish while simulants will have
polish lines, less lustre and more rounded facets that sometimes can be seen
with the unaided eye or through a jeweller’s loupe.

Another way to tell if you are looking at a round brilliant cut diamond, or a
round brilliant cut diamond simulant is to try the ‘see through effect’.
Place a diamond table (the top flat surface of the diamond) down on a printed
page and look through the pavilion, if you can read or see any of the type face
through the gemstone then you are not looking at a diamond but either a simulant
or synthetic diamond. While this test will not confirm you have a diamond, as
there are some simulants and synthetics that have no see through, you will be
able to eliminate the ones that do show see through.

Today, most jewellers and gemologists use a thermal testing device to tell if
the diamond is natural or not. The person who is examining the diamond touches
it with a probe that is connected to a meter that applies a small amount of heat
to the diamond and measures how quickly the heat is drawn away. The gauge
display usually consisted of a red and green zone. If the gauge stays in the
green zone it is a diamond, it continues moving to the red zone, it is a
simulant or synthetic diamond.

There are many other tests that require laboratory equipment to make a
determination. If you suspect a stone is not what it appears to be, take it to a
gemologist or send to a gemstone-testing laboratory such as GIA (Gemological
Institute of America) or EGL (European Gemological Laboratories) to have it
tested.

Lets take a look at some of the simulants that are around today, and have been
around for sometime. Glass has been used since the early 1700’s to simulate
diamonds and is still used extensively today in fashion jewelry. Colored Foil
was also used to produce color in glass simulants; it was attached to the back
of the glass giving the glass color when mounted in rings or pendants.

Zircon is a colorful or colorless natural gemstone that has been used for many
years as a diamond simulant, following these we have some more modern simulates
such as Synthetic Rutile both of these are doubly refractive, a tell tale they
are not diamonds. Strontium Titanate and YAG (yttrium aluminum garnet) are both
singularly refractive the same as diamonds and can be mistaken for diamonds if
not correctly identified using gemological equipment.

The last two are the most popular simulants of them all, Synthetic Cubic
Zirconia (CZ) and Synthetic Moissanite both are used extensively in the jewelry
trade. CZ is used extensively in less expensive jewelry and comes in a variety
of colors and quite durable (8.25 Mohr’s). Synthetic Moissanite (9.25
Mohr’s) has had a unique appeal in the jewelry industry, and is marketed as a
gemstone in its own right as well as being used as a diamond simulant.

Simulants provide inexpensive alternatives to diamonds and will continue to be
part of the jewelry industry. Now you know what simulants are you will be able
to make an informed decision if you decide to include them in your jewelry
collection. If you have some expensive diamond jewelry and don’t want to risk
wearing them daily, you can have a diamond simulant in a similar setting
providing you with a risk free alternative to wear daily.

Derek Parnell is a Graduate Gemologist (GIA) and owner of Jewels
by Truros a division of Truros Corporation. Truros Corporation has interests
in the Jewelry and the Real Estate Industry. For more information you can reach
Derek atJewels
by Truros.